Not sure what "rear camera on the rear view mirror means".
Our 2016 Era 70A has the backup camera mounted above the rear doors. The video is displayed on our in-dash Xite system (GPS, radio, etc.). There is no rear view mirror on the windshield, just the outside mirrors on the doors.
The backup camera is fully exposed to weather. Water leaked into it and ruined it so we wound up replacing it.
During the day the video quality is pretty good. Don't recall if it washes out much if the sun is behind us.
For some odd reason the video quality degrades at night, kind of foggy looking. Looked several times and there doesn't appear to be any moisture in it or anything to explain that.
We were looking into creating a sheet metal box to shade the camera and try to keep some water away from it but couldn't figure out an easy way to mount it and lost interest in doing it.